Carding machines



5, 1964 A. VARGA 3,145,425

CARDING MACHINES Filed on. 51, 1961 M/VENTOI? ANDR VARGA W mwfimak ATTORA/E Y 'and the calender rollers.

United States Patent 3,145,425 CARDING MACHINES Andre Varga, Toronto,Ontario, Canada, assignor to Carding Specialists (Canada) Limited,Toronto, Ontario, Canada Filed Oct. 31, 1961, Ser. No. 149,059 Claimspriority, application, Great Britain, Nov. 2, 1960, 37,609/60 1 Claim.(Cl. 1998) This invention relates to textile carding machines and to amethod of operating such machines. More particularly, but notexclusively, the invention is applicable to cotton type cardingmachines, that is to say, a machine having a single card clothedcylinder over which the material is passed, there being slow moving cardclothed flats or rollers or even stationary plates cooperating with thecylinder to perform the carding action.

The cotton type carding machines in general use are capable of producingonly a limited quantity of carded web per hour. Of course, this quantitycan be varied within limits according to the quality of the cotton orsynthetic fibres being carded, and the standard required of the finishedsliver delivered from the machine. Thus, for example, whilst a rate ofproduction of 5 pounds (weight) per hour would be quite normal for agood quality finished product, it is possible to achieve up to 20 poundsper hour production, if a substantial deterioration in quality isacceptable.

On the other hand, it is known that some increases in the speed of themachine does produce an increase in the strength of the yarnmanufactured from the carded material, and it is realised that anincreased production (though possibly accompanied by a decreased qualityof product) could be achieved by running the dolfer at much higherspeeds than normal, provided that some means could be devised forcontrolling the web issuing from the doffer. However, this has not beendone, because of the great difiiculties in controlling the web betweenthe dotfer The web tends to sag after it has left the doffer and at highspeeds the weight of web hanging between the dolfer and the calenderrollers would cause the web to collapse.

The present invention provides a means whereby a carding machine can beoperated to give a high rate of output.

According to this invention a method of carding textile fibres comprisespassing the fibrous material through a carding machine, the cylinder anddoffer of which are driven at high surface speed (as hereinafterdefined), passing the thin web of carded fibres leaving the dolferthrough the nip of a pair of ironing rollers, and subjecting theuncondensed web to a drafting action.

The normal speed of the cylinder in a conventional carding machine isaround 165 to 185 revolutions per minute, assuming the usual cylinderdiameter of approximately 50 inches. The normal speed of the doffer insuch a conventional carding machine is within the range of 7 to 16revolutions per minute, assuming the usual dotfer diameter ofapproximately 27 inches. Reference may be made to the publication TheCotton Spinners Pocket Book, Fourth Edition, by James F. Innes,published in 1947 by Sir Isaac Pitman and Sons, Ltd., London, England.

Reference has been made above to a high speed. It has been found that itis possible to operate the machine to give an output between 3 and 7times the normal output by using the method of controlling the webleaving the doffer in accordance with the invention. Thus, whilst it isa well known workshop practice to increase or decrease the dofier speedfor different fibres or different qualities and counts of finishedsliver, such variations in speed have been variations only in degree(e.g. 10 percent faster or 5 percent slower); but the high speeds"referred to herein are of a different order (e.g. I: times as fast asnormal). By high speeds, therefore, is meant a speed which is above theordinary range of workshop variations. As a rough guide, it may be saidthat the cylinder speeds are almost double or more than double thespeeds which would otherwise be employed for any particular fibre.

The ironing rollers employed must operate on the full width of thecarded web, and they may be of any known construction, but it ispreferred that they should be hard, smooth surfaced rollers. In order toproduce the drafting effect between the ironing rollers and the calenderrollers, the latter must be rotated at a higher surface speed than theironing rollers, and whilst the degree. of drafting can be variedsomewhat, a draft of 10 percent has been found satisfactory, but a draftof 30 percent is to be preferred. It must be emphasised that the combination of the ironing roller treatment and the drafting action isessential to provide the control required for the web coming oh? thedofier. It is preferred to apply such pressure to the ironing rollers aswill produce an ironing or smoothing effect on the individual fibres asthis improves the appearance of the finished yarns.

One practical application of the invention will now be described by wayof example only, with reference to the accompanying drawing which is adiagrammatic representation of a cotton type carding machine. For thisapplication, the machine used is an ordinary revolving flat cotton typecarding machine having the usual cylinder 10, flats 12, takerin roller14, and dolfer 16. All of these are card clothed, and it may bementioned here, that it is preferred to use metallic wire or saw toothcard clothing on the cylinder and/or doffer. It is also convenient touse a worker roller 18 in the are between the cylinder and the takerinroller. The cylinder 10 is 50 inches diameter and the doifer 16 is 27inches diameter.

A high speed fiy comb 20 is provided for removing the carded web fromthe doffer, but it will be understood that any method of stripping thedolfer could be employed. Immediately to the rear of the dolfer(considering the direction of movement of the material through themachine) there are a pair of smooth surfaced rollers 22 and 24 adaptedto press the web across its full width. These ironing rollers are gearedto the machine drive (not shown) so that their speed of rotation isrelated to the dolfer speed, and the gearing is preferably such that thesurface speed of the pressure rollers is greater than that of thedotfer. The usual condenser trumpet 26 and calender rollers 28 and 30are provided, and it is essential that the gearing between the ironingrollers and the machine drive is such that the calender rollers rotateat a surface speed which is greater than that of the ironing rollers toproduce the drafting effect, and in this particular example they arearranged to have a surface speed 30 percent greater than that of theironing rollers.

As there may be a tendency for some impurities and/ or fibres to stickto one or the other of the ironing rollers, means may be provided forkeeping them clear. For example, scraper blades may be pressed intoengagement with the surface of each roller, either by springs or byweighted levers or both. However, any other convenient means may beprovided for this purpose.

The ironing rollers may be cylindrical, but it may be desirable to makethem slightly barrel shaped to compensate for deflection when pressedtightly together and so ensure contact along the entire lengths of therollers. Another way of ensuring even distribution of pressure is toarrange the rollers with their axes slightly inclined to one another orcrossed that is, by swinging one roller about an axis whichis radial toboth rollers and passes through the mid point of both roller axes, suchan arrangement being described in the specification of BritishPatent'No. 697,106. vThe cylinder is rotated at a speed of 320revolutions per minute, and the doffer at a speed of 26 revolutions perminute. The speed of the flats and that of the takerin roller is notcritical, but is preferably greater than usual. It will at once beappreciated that these high speeds of the cylinder and doifer rollerscan be used to give a much greater ouput than conventional cardingmachines and carding processes. However, by providing the ironing rollerand drafting treatment of the Web, the latter does not collapse but canbe condensed into sliver in the usual manner.

Despite the high rate of delivery of the web, it has been found thatthere is no reduction in the quality of the product. In fact, there isan unexpected improvement attributable to the combination of thecylinder speed and the smoothing and drafting effect.

If the high speed of the cylinder is combined with a conventional rateof output (i.e. by not utilising the maximum potential of increasedproduction) it has been found i that the improvement in the quality ofthe web produced by the card can be much enhanced.

I claim:

A method of carding textile fibres comprising passing the fibrousmaterial through a carding machine, the cylinder and doffer of which aredriven at high surface speeds which are respectively up to about twiceand more and from 3 to 7 times the speeds normally employed for anyparticular fibre in known conventional carding machines, removing thematerial from the dofier as a thin carded web, passing the thin web ofcarded fibres leaving the doifer through the nip of a pair of ironingrollers and subjecting the uncondensed web leaving the ironing rollersto a drafting action sufiicient to cause relative longitudinal fibremovement in the web.

References Cited in the file of this patent UNITED STATES PATENTS VargaOct. 10, 1961

